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The globular cluster M13 in the constellation Hercules
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the Space Telescope Science Institute and NASA

Globular Clusters

If you think that this globular cluster looks like a very round elliptical galaxy, you would be right! Elliptical galaxies and globular clusters have a lot in common. There is no gas or dust in a globular cluster, and the stars are old. In fact, globular clusters may be the some of the oldest objects in the universe.

The big difference is size! Globular clusters contain hundreds of thousands or millions of stars. Elliptical galaxies can contain hundreds of billions of stars! And while elliptical galaxies are sometimes round, globular clusters are never elliptical.

Globular clusters are found both in spiral galaxies and elliptical galaxies. The Milky Way, for example, has over one hundred globular clusters throughout it's halo.

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The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA